Shrink tunnels for applying heat to shrink film diposed about a group of articles and having overlapped ends disposed below the article group are known. One difficulty which is characteristic of many such systems is due to the fact that shrink film tends to shrink too rapidly and become wrinkled in certain areas and, when so wrinkled, portions of the wrinkled areas become adhered to each other and thus result in an unattractive and possibly insecure container for the packaged articles.